A PSYCHIC who worked on the Murphys Creek murders has described the case as "one of the most horrific" she has worked on.

Debbie Malone, a Sydney-based psychic, was called in to assist in solving the 1974 murders of Sydney nurses Lorraine Wilson, 20, and Wendy Evans, 18, for the program Sensing Murder in 2004.

Lorraine and Wendy were holidaying in Queensland in September and October of 1974 and were reported missing on October 12, 1974.

Their remains were found on June 25, 1976 by two bush walkers who were walking in bushland at Murphys Creek near Toowoomba.

Mrs Malone described her experience in her new book Clues from Beyond.

"The Murphys Creek murders is one of the most horrific cases that I have ever worked on," she wrote.

"I will never forget being a psychic witness to the cruelty and barbarism the perpetrators inflicted on two innocent women."

As part of the program, she was given a "gold Victorian ring that had a crescent moon and little pearls around it" and was asked what she could see.

"I could see there was two girls, one taller girl and one shorter girl," she said.

"The taller girl with the long brown hair spoke to me the most and I realised she was the owner of the ring.

"They told me they were going on a holiday of a lifetime and I heard the word 'breakdown' and saw there was something wrong with the car.

"They told me that they hitchhiked and their parents had told them not to but they did. I could see they'd been picked up in a green and white Holden."

In the book, she gives detailed descriptions of the men she saw in the car with the girls, as well as what she believed to be the injuries and cause of death.

"Sexual assault - the words I was given were 'gang bang'," she wrote.

Mrs Malone's book, which is a follow up to her bestselling Never Alone, is a "fascinating insight to the valuable role psychic mediums play in solving crime and explores the truth about life and love, through the eyes of those in spirit".

It will be released in May by Rockpool Publishing and will retail for $29.99.